1. Field of the Invention
The present invention relates to a high-pressure injection system for internal combustion engines.
2. Description of the Background
GB-A-2 107 801 discloses a high-pressure injection system with a high-pressure pump having a plunger cylinder intended for an internal combustion engine, in which the pump delivers a pumped medium through a discharge port provided in a port element to a connection of a pressure line, which can be connected to an injector of the internal combustion engine. The adjacent sides of the high-pressure pump and the port element are designed as high-pressure sealing surfaces, so that the use of sealing elements can be dispensed with.
EP 0 915 252 A2 discloses a common rail injection system, in which a high-pressure pump delivers a pumped medium directly into a pressure chamber provided in the common rail. Injectors, through which the pumped medium stored in the pressure chamber can be delivered to the internal combustion engine, are also inserted into the common rail. In this solution, the plunger cylinder is inserted directly into the common rail, so that the use of a port element can be dispensed with.
An object of the present invention is to provide a high-pressure injection system, in which a high-pressure pump can be economically and tightly connected to a high-pressure line element. Another object of the present invention is to provide a high-pressure line element that can be used for a high-pressure injection system according to the present invention.
These objects and others can be achieved by providing a high-pressure injection system including a high-pressure pump having a plunger cylinder, the plunger cylinder having a delivery chamber and a high-pressure sealing surface on an outlet side, a port element arranged on the outlet side of the plunger cylinder and having a first end face and a second end face, the port element having an outlet port flow-connected to the delivery chamber and an outlet valve, the first end face of the port element facing the plunger cylinder, and a high-pressure line element arranged on an outlet side of the port element. The high-pressure line element comprises a high-pressure sealing surface. The high-pressure line element bears against the second end face of the port element. The port element is clamped between the plunger cylinder and the high-pressure line element. The first and second end faces of the port element each comprise a high-pressure sealing surface.
Also, the present invention includes a high-pressure line element including a pressure chamber serving for storage of a pumped medium which is fed into the pressure chamber by a high-pressure pump and fed from the pressure chamber to a plurality of injectors inserted into the internal combustion engine, and at least one cylindrical formed-on part configured to be connected to a high-pressure pump and having an admission port and a discharge port. The admission port is configured to feed the pumped medium carried in the high-pressure line element to the high-pressure pump, and the discharge port is configured to receive the pumped medium from the high-pressure pump to the pressure chamber.